how to make realistic water texture in blender 2.82
You can make your own transmissive water material and tweak settings,

But i prefer to install an free addon which is included in blender, it's called cycles material library or something like that.

There are many water materials available in it. 
You can find whatever that suits your needs.

You would not need to change anything if you are using cycles but IF YOU ARE USING EEVEE, 


You will have to turn on screen space refraction
You will have to change blend mode to alpha blend from opaque in your water material settings